1. Myofibrillar ATP consumption and isometric tension (PO) were determined in chemically skinned skeletal muscle fibres from human rectus abdominis and vastus lateralis muscle. Fibres were classified in four groups (I, II A, II B, II A/B or mixed) based on myosin heavy chain composition.2. ATP consumption (± S.E.M.) at 200C varied from 0-41 + 0-06 mmol F-1 s-5 in type IIB fibres (n = 5) to 0I10 + 0 01 mmol 1-' s-' in type I fibres (n = 13). 3. The ratio between ATPase activity and PO (tension cost) differed significantly between fast type II and slow type I fibres. At 120C tension cost was lower than the values found previously in corresponding fibre types in the rat.4. The relative increase in ATPase activity for a 10 0C temperature change (Q1o), determined in the range from 12 to 300C, was temperature independent and amounted to 2X60 + 0X06.The increase in PO with temperature was smaller and declined when the temperature increased. 5. From these measurements, estimates were obtained for the maximum rate of isometric ATP consumption and force development at muscle temperature in vivo (35 00).During muscle contraction, chemical energy in the form of adenosine 5'-triphosphate (ATP) is continuously utilized. A large proportion of the chemical energy is used directly for the interaction between the contractile filaments, the actomyosin interaction or cross-bridge cycle. Energetic studies performed on whole muscles or single fibres obtained from amphibians and mammals, together with biochemical studies on purified myosin and myofibrils, have provided a rather complete picture of ATP hydrolysis by the actomyosin interaction under steady-state conditions. Differences between isometric and isotonic conditions, effects of sarcomere length, temperature, pH and variations between myosin isoforms have been described (Fenn,

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Aims: To evaluate anti-diarrhoeal and growth enhancing properties of fermented soya beans in weaned piglets. Methods and Results: In a first phase piglet diet, toasted full-fat soya beans (20%) were replaced with either cooked soya beans or Rhizopus microsporus or Bacillus subtilis fermented soya beans. The effect on the incidence, severity and duration of diarrhoea in enterotoxigenic Escherichia coli (ETEC)-challenged weaned piglets was determined (pen trial, 24 piglets per treatment). Severity of diarrhoea was significantly less on the diet with Rhizopus-fermented soya beans compared with the control diet containing toasted soya beans. Piglets fed fermented soya beans showed increased feed intake (13 and 12%), average daily weight gain (18 and 21%) and feed efficiency (3 and 8%) (for Rhizopus and Bacillus-fermented soya beans, respectively). However, in the treatment groups an unequal mortality and a potential unequal distribution of receptor-positive piglets were observed. Conclusions: Cooked and fermented soya beans could be beneficial in the control of diarrhoea in ETECchallenged weaned piglets (particularly Rhizopus fermented) and significantly improved weight gain and feed intake (particularly Bacillus fermented). Significance and Impact of the Study: Fermented soya beans could offer benefits with respect to the control of diarrhoea and feed efficiency in piglets.

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